Straddling the Amazon and La Plata river basins, the Chiquitano dry forest covers
about 89 000 square miles (230 509 km2).

While the most environmental research in the region has focused on the effects of forest fires, SEI researchers and partners are studying how land use changes are altering the water supply.

Of particular interest are atajados, the surface storage ponds used for cattle watering that divert water from the natural water table.

Map showing communities sampled and groundwater storage ponds identified by SEI partners in the Amazon River Basin section of the Chiquitano dry forest in the Santa Cruz Department of Bolivia

Communities sampled by SEI partners in the Amazon River Basin section of the Chiquitano dry forest in the Santa Cruz Department of Bolivia. Source: Brazilian Shield data from Schenk et al. (1998).

Through remote sensing and on-the-ground surveys, researchers are working to quantify how much water is diverted through atajados and groundwater wells. These types of water extraction and storage can affect the natural hydrology of streams and downstream tributaries, as well as downstream users and ecosystems.

Local governments could benefit from more knowledge about the current and potential impacts of surface water diversions, particularly the role of atajados, and increasing groundwater extraction to better inform policy to regulate groundwater use.

Graphic representations showing how deforestation alters natural hydrology in an ecosystem

Conceptual model showing the effects of agricultural land use change and the development of decentralized surface water storage on the hydrologic water balance. Agricultural land-clearing and the use of atajados tend to reduce deep percolation and baseflow, while increasing surface runoff, affecting downstream water users and ecosystems.